Insulator



March 10, 1931. w, ESTORFF 1,795,939

INSULATOR Filed Aug. 3, 1927 INVENTOR Walther EstorPf 'ATTORNEY Pinned Mar. 10, 1931 UNITED STATES PATENT OFFICE WALTHEB 128130331, 01 BERLIN-CHARLOTTENBUBG, GERMANY, ASSIGNOB TO WEST- INGHOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORATION 01' PENN- SYLVAN IA.

INBULATOB Application filed August 8, 1927, Serial No. 210,268, and in Germany November 18, 1988.

My invention relates to insulators and particularly to insulators of the high-voltage t pe.

In insulators for spacing or connecting conductors of different potentials, a higher electrostatic flux density occurs adjacent to the positions-of engagement between the conducting and non-conducting members which sometimes results in discharges or breakdowns between the conductors along the surface of the insulating or dielectric member.

It is one of the purposes of my invention the surface creepage and internal-capacity currents are caused to traverse substantially sinuous paths between the conducting members to materially improve the operation of the insulator.

With such objects in view, as well as other advantages WhlCll may be incident to the utilization of the improvement, the invention consists in the parts and combinations thereof hereinafter set forth and claimed, with the understanding that the several necessary elements constituting the same may be varied in proportion, arrangement and-texture without departing from the nature and S00 e of the invention.

igure 1 of the accompanying drawing is a cross-sectional side view of a device embodying my invention, and

Figs. 2 and 3 are views taken at right angles to Fig. 1, along the lines IIII and IIIIII, respectively.

The device comprises, in general, an elongated conductor 2, an insulating member 3 surrounding the conductor 2 and a. conductor 4 surrounding the conductor 2 and the insulating member 3 in the form of a tube or casing adapted to contain a fluid insulating medium 5, such as oil.

The conductor 2 may be in the form of a cylindrical rod or tube which is engaged by an annular terminal portion 7 of the insulating member 3.

The insulating member 3 further comprises an outer terminal portion 8, engaging inner surfaces of the conductor 4 and disposed in concentric or radially .alined relation to the opposite terminal portion 7.

A portion 9 of the member 3, of substantially U-shape in longitudinal cross-section, connects the terminal portions 7 and 8'at one side thereof.

The portion 9 may be provided with apertures 10 to permit free circulation of the oil 5 therethrough.

In the above-described structure, were the portion 9 to be omitted and the portions 7 and 8 directly connected to each other, relativeshort direct discharge paths would be provided radially along the sides of the member 3 between the members 2 and 4.

By my invention, an insulating medium, different from the material of the member 3, is placed in series with this material along, or in the direction of, the above-mentioned direct-discharge path, whereby the insulating characteristics of the insulating surface are materially improved.

In counterdistinction to usual insulators, whether they have surface corrugations or not, the insulator of my invention employs media along the most direct breakdown path, of different insulating characteristics and causes both the surface-creepage'and the internal-capacity currents of the member 3 to traverse sinuous paths whereby a substantially maximum advantage is taken of the space or direct-line path between the members 2 and 4.

lVhile I have shownand described a particular form of my invention, changes may be effected therein without departing from the scope and spirit thereof, as set forth in the appended claims.

I claim as my invention:

1. An insulator comprising spaced terminal portions and a connecting portion therefor of substantially U-shape extending lat orally thereto entirely at one side thereof and having each leg of said connecting portion disposed inwardly with respect to its corresponding terminal portion toward the other terminal portion.

2. An insulator comprising spaced, coaxial, annular terminal portions and an annular perforate connection portion therefor of substantially U-shape in radial section extending laterally thereto and disposed entirely at one sidethereof.

3. An insulator comprising spaced substantially concentricannular portions and a prising a dielectric member. embodying spaced annular radially-opposite terminal portions and a portion of substantially U- shape in cross section connecting the same entirely at one side thereof and having each leg disposed inwardly with respect to its corresponding terminal toward the other terminal. I

5. An insulator for radially spacing telescopically-related conducting members comprising a dielectric ring member having sub stantially radially-opposite spaced annular terminal portions and an annular portion of substantially U-shape in cross section connected to said termlnal portions entirely at one side thereof and having each leg disposed inwardly with res ect to its corresponding terminal towar the other termivnal.

6. An insulator for radially spacing telescopically-related conducting members comprising a dielectric ring member having substantially radially-opposite spaced annular terminal portions and an annular portion 'of substantially U-shape in cross section con-- nected to said terminal portions entirely at one side thereof, said annular portion of U- shape having fluid ducts therein and each leg disposed inwardly with respect to its correspondingterminal toward the other terminal.

7. An insulator comprising a dielectric member having spaced substantially concentric ring-like terminal portions, a tubular portion of smaller diameter than the outer of said ring portions projecting coaxially from one sidethereof, a second tubular por-' tion similarly projecting from adjacent to I the outer perimeter of the inner of said ring portions in coaxial relation to said first tubular portion and ortions connectin the outer ends of sai tubular portions or supporting the ring and tube tions in spaced relation and perm tting uid flow longitudinally through the space between the tube and ring portions.

8. An insulator comprising a substantially uniform cylindrical disc 0 dielectric material having a central opening therethrough and an annular opening therethrough between said central opening and the outer perimeter of the disc, a pair of coaxial tubular portions projecting from one side of the disc at opposite sides of said annular opening, the outer of said tubular portions being of smaller exterior diameter than the diameter of the disc and the inner of said tubular portions being of greater interior diameter than the diameter of said central opening, and an apertured annular portion oining the outer ends of saidtubular portions to position the same relative to each other and to permit fluid flow longitudinally between the tubular portions through said annular opening.

9. An insulator comprising a dielectric member embodying coaxially-related radially spaced tubular portions joined at one end by portions permitting fluid flow therethrough and between the tubular portions and including substantially concentric annular lateral flanges projecting inwardly from the other end of the smaller tubular portion and outwardly from the correspond ing end of the larger tubular portion, respectively.

10. An insulator comprising a dielectric member embodying coaxially-related radially spaced tubular portions joined at one end by a substantially toroidal portion having perimetrally-spaced longitudinal openings therethrough between the tubular portions and including substantially concentric annular lateral flanges of rectangular crosssection projecting inwardly from the other In testnnony whereof, I have hereunto subscribed my name this fourth day of July,

' VVALTHER ESTORFF. 

